I have a 1999 F150 4x4 Supercab. Friday night I got home and shut the headlights off and turnt the truck off. When I looked up my lights were still on. Played with the switch, would not shut off. Only the headlights were on, parking lights and dash lights would not come on. Had to pull the fuses for the low beams to shut off the lights. Made a few calls and figured must be the headlight switch. Installed a new headlight switch yesterday, put fuses back in and the lights came back on and the switch was off. Still no parking lights, chimes, etc. If I throw the highbeam switch to high beams they come on also without the truck running, and I the fog lights work on the switch. Any ideas??

 

do you have day time running lights? if so, i have seen the module go bad and keep the lights on like you say. if you do not have drl. then the only thing is the multifunction sw. or if you have auto light. then could be the relay sticking. from your story you dont have auto. so i would say mulit sw. good luck

 

Wino, thanks for the input. Can you enlight me on why you say the mutli switch. How or why would that effect the parking/taillights? Is there a headlight relay? I can not find anything in the book that shows a headlight relay, only autolamp relay?

 

Hey, I just saw your post and I had the same problem with my 2000. The autolamp relays are what are giving you the problems.

What I ended up doing was popping the long narrow oval cover off the passenger side of the dash that will let you get to some wiring harnesses and a relay block. The relay block has a black plastic cover that will come off with some persuasion. It's just held on by some plastic clips, but I had troubles getting it out of the close quarters.

Anyway, under the cover there are locations for 4 relays. Only 3 of these are used though, 1 is for the 4x4 system and the other 2 are for the optional autolamp system, 1 for headlights, 1 for parking/dash lights. Even though my truck doesn't have autolamp, the relays were installed. I pulled the two relays, and no more phantom headlights/parking lights. The lights still work like they're supposed to though.

Let me know if you need a better explaination of what to do.

Sven

 

sorry took so long for me to get back to you. i have been hunting. if you have auto lamps. then there are relays that can stick. like f150sven says his did. if you have regular light sys. there are no relays. just fuses. the only thing in a reg sys that changes. is the multifunction sw and the head light sw. and you replaced head light sw. the mutifunction sw controls high and low beam. also you flash to pass. so it can do some funny things. if you have auto lamps. look at the relays like f150sven. i have not got into the sys. to check. but if you have reg lights. those relays should not be there. as per the book. so reading f150sven story. im going to check this out. i hope you got your rig going by now. and all you troubles are gone, hehe. good luck

 

My truck does not have the autolamp feature, but DID have the relays installed. sleisey emailed me the other day, and his truck was the same way. Some bean counter at Ford missed this one. Hard to believe they put the extra relays in every truck.

BTW wino,
The relays were not sticking they would click on and off as I pulled them out. Something upstream of the relays was the actual cause of the problem. I haven't investigated any further since pulling the relays took care of the light problem.

 

thanks. that's good input. i need to keep that in mind. the book shows nothing. well like you said bean counters. hehehe
thanks again.